Hello Kim,
this topic was part of the new PP - MES integration for EhP6, please refer to SAP_APPL 606 release note "MES Integration for Production Order". But since BAPI interface tables cannot be switched via business function this functionality is also available even if no PP - MES integration is active/used. A detailed docu is attached to the interface tables of almost every PP confirmation BAPI. Hope this helps.
Andreas